Set inside Eagle's Junior High School during the 1960s, Horror Nun follows a student lured to a summer camp that turns out to be a trap.

Sister Madeline, the head of the nunnery, has kidnapped you — and the school's locked corridors, hidden rooms, and dark secrets stand between you and escape.

The premise draws loosely from the Evil Nun franchise originally created by Keplerians Horror Games, a Spanish indie studio behind titles with over 50 million downloads. What makes this free online game compelling is its restraint.

There is no constant combat or scripted jump scares driving the tension. Instead, Horror Nun relies on sound design, patrol patterns, and environmental puzzles to build dread.

Multiple escape routes, hidden lore, a competitive leaderboard, and five difficulty levels give the game strong replay value as a browser game. Built with HTML5 (Unity WebGL), it loads instantly on desktop, mobile, and tablet without any additional software.

Horror Nun features two distinct modes with separate control layouts. The reference sources show slight variation in key bindings across platforms, so check the in-game tutorial if a key feels unresponsive.

Escape Mode focuses on stealth and puzzle interaction: Some browser versions may map interact to E or left-click instead of F. If controls feel off, try both. Your goal is to leave Eagle's Junior High School alive.

The school contains locked doors, electrical systems that need restoring, and items scattered across classrooms, kitchens, and hallways. You must explore, collect tools, and solve layered puzzles to unlock one of several escape paths.

The main door escape, for example, requires finding a Small Cable, installing it in the Electric Panel, opening the Automatic Blind, retrieving a Broom, then using it on a rotten ceiling in the secretary room to drop a Cookies Box.

That box must be thrown from the Balcony to the basketball court below, where it reveals the Main Door Key. Other routes lead through the parking area and involve entirely different item chains. Sister Madeline patrols the school and reacts to sound. Getting caught ends your run.